Height adjustable saddle pole

ABSTRACT

The invention relates to a height adjustable saddle pole consisting of two tubes which are telescopically slidable into another, that is to say a cladding tube for accommodating a saddle support tube, whereas the saddle support tube is spring-loaded and is fixed in position via a locking pin. The bores into which the locking pin engages, are located in the region of the smallest stress of the saddle support tube in order to weaken the static of the saddle support tube as little as possible.

The invention relates to a height adjustable saddle pole (S) consisting of two tubes which are telescopically slidable into another, that is to say a cladding tube for accommodating a saddle support tube, a spring element acting upon the saddle support tube, a locking device, which is installed on the cladding tube with a locking pin, a guide for the locking pin, means for adjusting the locking pin in a latched position and an unlatched position, whereas the locking pin is moved orthogonally with respect to and in the direction of the axis of the saddle support tube whereas at least two axially spaced apart bores are provided in the saddle support tube for accommodating the locking pin and whereas the locking pin in the latched position engages into one of the bores through a recess of the cladding tube and thus completely absorbs the axial forces of the saddle support tube (16).

Saddle poles for fastening bicycle saddles are usually fixed in the saddle tube with a mechanical clamp. Consequently, the saddle tube is generally slit at the upper end so that the periphery of the tube is reduced by the clamping effect and thus the saddle tube bears upon the saddle pole with a positive fit. The clamp is tightened with a nut or a quick clamping device is used, at which the clamping force is reached by changing the position of a lever. Such a “quick release lever” enables to adjust the height of the saddle and to fix it without tool. Such is for example necessary if the bicycle is going to be ridden by people of different size or if the saddle should be adapted for one and the same rider using certain parameters. Such is the case for instance when riding in difficult terrain, as in particular in mountain biking with mountain bikes. Uphill, the height of the saddle must be adjusted optimally from an ergonomic viewpoint so as to achieve good power transmission. When going downhill, the rider must shift his centre of gravity backwards and downwards according to the steepness and to the difficulty and for that purpose he must often bring his buttocks behind the saddle. The deeper the saddle, the easier the rider can shift his centre of gravity actively and dynamically, but thereby also loses on cornering forces which he can press with the inside of its thighs against the saddle when the latter is accordingly in a raised position The optimal height of the saddle therefore depends on the respective riding condition.

The shortcoming of the described clamping device lies in that the rider must dismount every time he needs to adjust the height and driving direction of the saddle. To make this adjustment easier it is suggested in the German disclosure DE 4237864 A1 to provide a lateral locking pin with which the position in height of the saddle pole can be fixed. This locking pin is however used solely for fixing the height of the saddle pole, whereas conversely the locking mechanism operates in the axial direction and thereby the axial load has conventionally been absorbed by means of a clamping device, hence in a friction locking manner. The rider still needs to dismount for adjusting the height of the saddle pole.

It would hence be desirable to provide a device for adjusting the height of a bicycle saddle, which the rider can adjust without having to dismount.

Height adjustable saddle poles are disclosed in the state of the art which function after the principle of hydraulic locking. The saddle poles described in the German utility model DE 20 2007 014515 U1 (Kindshock) or in the document U.S. Pat. No. 7,083,180 B2 (Paul Turner) operate with two oil chambers which are connected to one another by a valve. A tube can be moved up and down in the shank by opening the valve with the trigger. The lower oil chamber is additionally filled with air so as to generate a force upwards. Consequently the pole is pressed upwards by pulling the trigger and releasing it simultaneously. The trigger is always actuated at the upper end of the saddle support tube via a lever. Said lever can be actuated manually directly on the head of the saddle pole. Alternately, a Bowden cable can be provided from the handlebar for remote actuation of the device via an appropriate mechanism. With the embodiments available on the market at the moment and described above, the adjustment range is currently 125 mm max.

The shortcoming of this pole is the relatively complex structure of the hydraulic system. Furthermore, the hydraulic medium required in the system increases with the adjustment range and so does the weight of the system. An additional shortcoming due to the system is the necessary mounting of the actuating lever on the saddle head. If said lever should be actuated via a remote control on the handlebar the mechanical, hydraulic or electric control cable provided to that end must follow the adjustment stroke of the saddle pole.

A height adjustable saddle pole is disclosed in the international patent application WO 2007/117884 A2 with which a bolt is brought into a recess of a saddle support tube, through a recess of a cladding tube, in a latched position from the outside. The bolt is operated by means of a magnet for adjusting the saddle pole. The mechanism is designed in such a way that the shear force maintains the locking bolt in the locking position as long as the bolt can be loosened by the own weight of the rider. It is hence not possible for example to adjust the height of the saddle pole when the rider is standing on the pedals. Moreover, the mechanism is relatively expensive and the bores are located on the front or on the back in the driving direction, so that the static of the saddle support tube is weakened maximally.

Another mechanical locking is disclosed in document U.S. Pat. No. 6,354,557 B1 (RASE). In that case, a longitudinal groove is inserted into the saddle support tube which also weakens the saddle support tube strongly. The height adjustable saddle pole for a bicycle, disclosed in the German patent specification DE 198 55 161 C1 admittedly has a lateral locking system, but operates with three tubes which are telescopically slidable into another, whereas the tube of the saddle pole has a continuous longitudinal groove in the region of the largest stress, i.e. in the driving direction, which causes maximal weakening of the saddle pole and consequently rules it out for saddle poles with which minimal weight and high mechanical stability are required.

All the height adjustable saddle poles known to the applicant, which operate after the principle of a locking mechanism by means of a locking pin, integrate the bores necessary to that end from the front or from the rear (as seen in driving direction) into the saddle support tube, or exhibit (as the DE 198 55 161 C1 mentioned) additional weaknesses in the area of the largest bending stress. An exception is provided in the German utility model DE 20 2008 015 968 U1, in which the locking is more precisely performed laterally, the locking bolt however engages tangentially with respect to the saddle support tube into an accordingly deepened recess, whereas such bolts are provided with smaller depth between the deepened recesses, into which the accordingly shaped bolt (with two diameters) engages during the height adjustment and hence simultaneously forms an anti-twist device. The tangentially arranged recesses reach further into the region of the increasing bending stress and hence cause more significant weakening compared with simple bores, they are also more difficult to realise than the latter from a manufacturing technical viewpoint.

If the bores necessary to the locking mechanism or recesses of other types are incorporated in the front or rear area of a saddle support tube as seen in driving direction—this is here (relative to the mechanical stability of such a construction) the most inappropriate position for these recesses, since the bending stresses induced by the operational forces reach a maximum in this area. Tests have however shown that with the materials known at the moment and rationally usable for saddle support tubes, which first and foremost with mountain bikes must meet the requirements in terms of robustness, lightweight and operational stability, the saddle pole is weakened by the bores to thet extent that the tube may break or buckle. The weakening of a saddle pole grows exponentially when the recesses are located on the front or on the back, compared to recesses located laterally. With a targeted adjustment stroke of more than 150 millimetres the current tests for saddle poles of mountain bikes, developed by testing agencies, are not passed with such a construction in which the recesses are located on the front or on the back. These tests are performed with simulation of the forces prevailing during riding. It should be noted that the saddle pole is not clamped or fixed in a friction locking manner any longer with these systems, but in fact the load is only absorbed by the locking mechanism in direction of the axis of the saddle pole or of the saddle support tube. The saddle support tube is not fixed any longer in the transition region between saddle support tube and cladding tube.

The object of the invention is hence to remedy the shortcomings aforementioned.

Another purpose of this invention is to provide a pole which is of simple design and easy to maintain, and which allows for adjustment ranges with a lift of more than 150 mm.

The invention should besides provide a solution for a remote control cable running parallel on the cladding tube.

The object is satisfied in that the bores for accommodating the locking pin are located in the area of the smallest stress of the saddle support tube. In the context of the patent application, the term “bore” should be understood as a recess, i.e. it need not strictly be a circular hole but also other geometrical recesses can be provided, for example also conical recesses and/or blind hole-shaped recesses, etc. In the context of the patent application, by “region” is meant that the centre of a bore or recess need not exactly coincide with a point of the neutral fibre, but that it is important to arrange the recesses in regions which do not weaken the saddle support tube so much.

The stress in a saddle support tube is generated by the load of the rider, whose weight force pushes the saddle support tube backwards and downwards. This is due to the fact that the saddle tube (this is the tube of the bicycle which receives the saddle pole) extends obliquely from the receiving opening of the saddle pole forwards and downwards to the bottom bracket bearing. The tensile stress is therefore maximum in the front fibre of the saddle support tube in the driving direction (the compressive stress is accordingly maximum in the rear fibre in the driving direction). The “neutral” fibre of a saddle support tube lies laterally offset by nearly 90 degrees from the maximally stressed fibres. The region of the neutral fibre is hence the region of the smallest stress and hence the optimal region for mounting the locking device.

Due to the bending load, the saddle support tube and hence the bore of the saddle support tube move marginally backwards (indications such as “backwards”, “forwards”, “laterally” are always related to the driving direction), so that the latched locking pin under load is pushed in this direction. It is hence advantageous that the locking pin in the latched position accompanies the movement of the saddle support tube more or less in the direction and in the opposite direction of the cross product of the vector of the longitudinal axis of the cladding tube with the vector of the longitudinal axis of the locking pin. The degree of freedom of the locking pin can be achieved through suitable mounting of the locking pin or its guide.

According to a further advantageous embodiment of the invention, the locking pin has a first flattening or phase in the peripheral area of its front end. The locking pin can hence be latched in the bore more easily.

It is particularly advantageously if the locking pin in the partial regions of its periphery, on which the bores of the saddle support tube have the largest relative movement with respect to the locking pin, contains second larger flattenings so that latching is then secured when the deflection of the saddle support tube is maximum.

It is further advantageous if the contour of the locking pin on its front end matches the contour of the saddle support tube. The locking pin lies thereby already over its surface on the saddle support tube and can hence be brought in the latched position faster, not to mention the release which is also facilitated. All the more so if implemented in combination with the flattenings.

According to a further advantageous variation of the invention, the locking pin is arranged in such a way that it absorbs the load in direction of the longitudinal axis of the cladding tube (28) or of the saddle support tube over its surface in its guide. In the axial direction, the locking pin must absorb almost the whole weight force of the rider. The force should therefore be absorbed flatly as far as possible, preferably by a plane surface area.

The locking pin can hence advantageously be brought into the latched position and into the unlatched position. It is hence meaningful since the force which has to be exerted can be transformed with a lever.

The locking pin should consequently allow the movement of the bore which is caused by the load of the saddle pole.

In a further advantageous embodiment of the invention, the adjustment of the locking pin is done via a slotted guide mechanism. Such a mechanism allows on the one hand to achieve a particularly small design and on the other hand the distance-force curve can be set up and optimised via the design of the sliding path.

The size of the structure of the whole device can be reduced particularly advantageously in such a way that a portion of the mechanism for actuating the locking pin is arranged around the periphery of the cladding tube.

In an advantageous variation of the invention, the locking mechanism is actuated via a Bowden cable. According to the state of the art, shifters or similar actuating devices are provided for actuating such a Bowden cable, which can be fixed to the handlebar of a bicycle, so that the rider can release the height adjustment mechanism during riding. By reversing the actuation of the latching mechanism for example, by means of a curved disc, it is possible to bring the Bowden cable close to the cladding tube or the saddle tube from below, so that it does not interfere with the rider.

An advantageous variation of the invention consists in that the spring element acting upon the saddle support tube is a pneumatic spring. This enables to achieve a relatively flat spring characteristic and a practically constant extension force as well. Such pneumatic springs are commercially available at low cost.

In a further advantageous embodiment of the invention, the cladding tube is the saddle tube of a bicycle. There is consequently no need for an additional tube as a cladding tube and the design of the device can be easier. The saddle tube should indeed be prepared “in factory” accordingly.

According to another advantageous embodiment of the invention, means should be provided to prevent any twisting of the saddle support tube with respect to the cladding tube. This substantially facilitates the adjustment for the rider while riding, since otherwise the saddle might easily be twisted during the adjustment and the locking pin would not latch.

An advantageous variation of the invention consists in that a pinhole closure is provided for sealing the bores which opens in reaction to the force of the locking pin 61. This prevents the ingress of dirt through the bores.

It is further advantageous that the upper end of the external tube of the pneumatic spring or gas spring is fixed at the upper end of the saddle support tube. This hence prevents the saddle pole from falling out or being removed completely. This enables moreover to define the end stop of the maximum extended position of the saddle support tube, which is also adjustable in height through the setting of the pneumatic spring.

An advantageous variation of the invention consists finally in that a wiping device is provided, which contains a felt ring 3. This prevents the ingress of dirt. The felt ring can be soaked with oil so that the saddle support tube is coated with a thin oil film due to the up and down movement and thus absorbs less dirt. Better sliding properties can thus also be obtained.

An exemplary embodiment of the invention is described below using drawings. Wherein:

FIG. 1 shows a cut-out of a bicycle frame with a height adjustable saddle pole fitted with a saddle

FIG. 2 shows a device for height adjustment of a saddle pole in assembled condition

FIG. 3 shows an exploded drawing of the locking device V with cladding tube 28, etc.

FIG. 4 shows a part of the exploded drawing according to FIG. 3

FIG. 5 shows the locking device in latched position

FIG. 6 shows the locking device in unlatched position

FIG. 7 shows the locking pin 61 in enlarged view

FIG. 8 shows a cut D-D through the locking device V

FIG. 9 shows an exploded drawing of the locking device V

FIG. 10 shows a height adjustable saddle pole with the forces acting upon it

FIG. 1 shows a cut-out of a bicycle frame along with a schematic view of a height adjustable saddle pole fitted with said saddle support tube 16 and said saddle plate SA. The locking device V is here only schematically indicated. A pneumatic spring GF is situated inside the saddle support tube 16. A Bowden cable 30 leads from the locking device V along the upper tube OR of the bicycle frame to the handlebar L and there terminates at the lever H. The locking device V can be released by actuating the lever and the saddle pole S pushed downwards by the weight of the rider or extended when relieved from his weight while riding, whereas both his hands can stay on the handlebar L. The structural design of a corresponding remote control (lever H plus Bowden cable) is known to the man of the art. A current spiral spring etc. can be also used instead of a pneumatic spring GE

FIG. 2 shows a device for height adjustment of a saddle pole in assembled condition fitted with a saddle plate SA on which a conventional saddle can be fastened. The saddle support tube 16, not visible here, is mounted telescopically in the cladding tube 28. The cladding tube 28 is closed up at the lower end with a clamping nut 15 which for instance can be screwed with the cladding tube 28 by means of a thread.

The locking device V, to which the saddle support tube 16 is fixable relative to the cladding tube, is installed at the upper end of the cladding tube 28. The locking device V can hence be formed in one piece, but it can be installed as a separate component on the cladding tube 28 for example by gluing. The Bowden cable 30 is fastened at the bottom of the locking device V. The locking device V is provided with the cover 5 of the base body GK.

FIG. 3 shows an exploded view of the locking device V which is fastened to the cladding tube 28, only shown as a cut-out. The locking device V (the base body GK of the locking device V can be seen) is hence arranged around the cladding tube 28 in the form of a quarter circle. The base body GK has a guide for the slotted slider 9. The pressure springs 10 of the slotted slider 9 are supported at the lug 92 of the slotted slider.

The locking pin 61 is received by the guide 52 via the roller 8. The tilting lever 6 is articulated at the axle 65 of the locking pin 61. The axles 66 of the tilting lever 6 are received in a recess 71 of the base body GK via the rollers 7. The whole pin consists more advantageously of a high performance plastic, which on the one hand meets the requirements in terms of solidity and on the other hand has good sliding properties as regards its guiding means.

The Bowden cable holder 27 is mounted on the right side of the base body GK by means of the fastening screws 271. The Bowden cable holder 27 forms a cavity together with the base body GK, which serves as a guide for the slotted slider 9. It also receives the Bowden cable 26. The slider 273 is actuated via the Bowden cable 26 and engages with its roller 272 into the slotted guide 91 of the slotted slider 9.

FIG. 3 also shows a pre-wiper ring 1, a wiper ring 2, a felt ring 3, a clamping nut 4 as well as a plastic bush 23. Pre-wiper ring 1, wiper ring 2, felt ring 3 and the clamping nut 4 form a wiping device 11. The pre-wiper ring 1 should hence wipe the coarse dirt, when the saddle pole is pushed downwards. The wiper ring 2 then takes over the precision work. The use of the felt ring 3 is particularly advantageous. It can be soaked with oil, so that the saddle support tube is always wetted with a thin, dirt repelling oil film.

The plastic bush 23 enables the saddle support tube 16 to slide in the cladding tube 28 easily. It also absorbs the radial forces of the saddle pole. The pre-wiper ring 1 is screwed on the clamping nut 4 and hence fixes the wiper ring 2 and the felt ring 3. The clamping nut 4 itself is screwed on the cladding tube 28 and hence fixes the plastic bush 23.

FIG. 4 shows an enlarged part of the exploded drawing according to FIG. 3. The parts already known from FIG. 3 are indicated by the same reference signs. The locking pin 61 is represented together with the tilting lever 6 and the slotted slider 9 assembled together. The locking pin 61 has in its guide 52 a clearance in the direction of the double arrow SP, whereas the direction of the double arrow SP results from the cross product of the vector of the longitudinal axis A28 of the cladding tube 28 with the vector of the longitudinal axis A61 of the locking pin 61. The locking pin 61 can thus rotate in its guide 52 about its axis 65. Due to the linear movement of the slotted slider 9 and to the radial movement of the tilting lever, the differences in length generated during the movement of the bike must be compensated for. To that end the recess 71, into which the axle 66 of the tilting lever 6 engages by means of the roller 7, is formed accordingly and the axle receptacle of the tilting lever 6, which receives the axle of the slotted slider, is designed as a long hole. The locking pin 61 conversely is run via its shaft cylinder roller 67 in the guide groove 68 in such a way that it has no lateral play. But it is also possible to fix the axle 66 of the tilting lever 6 free of play in the recess 71 and to form the axle receptacle of the tilting lever 6, which receives the axle of the locking pin 61, also as a long hole.

FIGS. 5 and 6 show the locking device V in installed condition with cut-open Bowden cable holder 27, for better distinction of the position of the sliding mechanism. FIG. 5 shows the locking device V in the latched position and FIG. 6 shows the locking device V in the unlatched position. In the latched position according to FIG. 5, the slider 273 attached to the Bowden cable 26 is pushed into the upper position via the compression spring 274 and has pushed the slotted slider 9 over the slide 91 outwardly in such a way so that the pin 61 has been pushed inwardly over the tilting lever 6. In the illustration according to FIG. 6, the Bowden cable 26 has been clamped against the force of the compression spring 274 so that the slider 273 is pulled downwards and the slotted slider 9 is brought inwardly against the force of the pressure springs 10, not visible in FIG. 6.

FIG. 7 shows the locking pin 61 in enlarged view. It has a cuboidal body 611, on which the axle 65 is moulded. The cuboidal body 611 is rounded on its longitudinal sides for manufacture-technical reasons. A cylindrical lug 62 is mounted on the front end of the locking pin 61. This lug 62 has a flattening 63 on its front circumference. The bores 29, 29′, 29″ shown on FIG. 8 can thus be latched into more easily. Second flattenings 64 are arranged laterally on the lug 62, which are larger compared with the first flattenings 63. This measure is therefore taken because the locking pin 61 in its initial position could be rotated maximally about its axis. The second flattenings 64 also provide for reliable renewed latching of the pin.

FIG. 8 shows a sectional view D-D of the locking device V. An important point of the invention should be mentioned now, namely, that the driving direction is illustrated in the direction of the arrow F and which locking pin 61 engages from the side, that is to say 90° offset with respect to the driving direction. The base body GK is here formed as a single piece around the cladding tube 28 and fastened thereto for example by gluing. The locking pin 61 can run freely in its guide 52 and be brought into engagement into the bores 29, 29′, 29″ of the saddle support tube 16. Three guide grooves 171 for the sliding blocks 17 (FIG. 9) are inserted into the cladding tube 28 to prevent any twisting of the saddle support tube 16 with respect to the cladding tube 28. The contour of the front end 62 of the locking pin 61 matches the contour of the saddle support tube 16, so that the locking pin 61 bears upon it directly.

The section D-D shows a pinhole closure 22, whose three-dimensional representation is shown in FIG. 9. This closure is for example made of plastic and enables to close the bores 29, 29′, 29″ hermetically and hence to prevent the ingress of dirt. Such pinhole closures 22 should preferably be provided for the bores 29, 29′, 29″ which may be situated outside the cladding tube 28, but a pinhole closure 22 can also be provided for each bore. A countersink 291 can particularly advantageously be inserted in the saddle support tube 16, for example by drilling or milling, for fixing the pinhole closure 22. The latching lug 221 of the pinhole closure 22 latches into this countersink 291. The insertion of the countersink 291 is particularly straightforward since it lies directly opposite the respective bore 29, 29′, 29″. It is moreover also situated laterally in the driving direction so that the weakening of the axial resistance torque (as already mentioned above) in the load direction is negligible.

FIG. 9 shows the whole device for adjusting the height of a saddle pole in exploded view. There is no need to go into the components described already in combination with FIGS. 1-8. The driving direction is again indicated by the arrow F on the receptacle for the saddle SA and it can be clearly seen that the bores 29, 29′, 29″ are inserted into the saddle support tube 16 at right angle to the driving direction F.

The exploded drawing according to FIG. 9 additionally shows the components of the pneumatic spring, that is to say the piston 12, the piston rod 13, the pneumatic spring outer tube 20, the resilient seal 21, the cover 19, the pneumatic spring GF and the fastening screws 24 of the pneumatic spring. The pneumatic spring GF is centred in the cladding tube 28 with the adjustment disc 14. The sliding blocks 17 as well as a pneumatic spring holder 18 are further mounted on the saddle support tube 16. A guide bushing XX is mounted on the lower end of the saddle support tube to absorb the load of the stressed saddle pole 16. The pinhole closure 22 described using FIG. 8 is designated by the reference sign 22.

The pneumatic spring outer tube of the pneumatic spring GF (FIG. 1) is fixed in the saddle support tube 16 by means of the fixing sleeve 18. To do so, the fixing sleeve 18 is fastened on the top in the saddle support tube 16 for instance by gluing and the gas spring valve 25 inserted from below through the fixing sleeve 18, which is formed accordingly, and fixed from above with the fastening screw 24. This has the advantage that firstly the saddle support tube 16 cannot come out of the cladding tube 28 completely and secondly the pneumatic spring GF establishes the end stop of the maximum extended position. This end stop is moreover adjustable in height through the setting of the pneumatic spring GF.

FIG. 10 shows the forces acting upon the saddle support tube 16 and the cladding tube 28. (Indications below such as back, front, laterally, right, left, etc. always refer to the driving direction, as shown by the thin arrow above the saddle tip). The force FF caused by the rider is regularly exerted against the driving direction, backwards and downwards. It finds a counter-bearing at the upper rear end of the cladding tube through the force FHO as well as in the front area of the cladding tube 28, against which the guide bushing XX, which is situated at the lower end of the saddle support tube, are pushed by the leverage effect (force arrow FHN). The resulting force FV in the axial direction downwards is absorbed by the locking pin 61 (not illustrated here) The result is thus the stress curve indicated schematically in the saddle support tube 16, which is a superposition of compression and bending stresses. There is an increasing tensile stress ZS towards the front area of the saddle support tube 16 away from the neutral fibre NF while the compression stress DS increases with the distance from the neutral fibre NF opposite to the driving direction. The portion of the compression stress DS is greater in the upper section than in the lower section due to the short lever length of the radial force components. Consequently, the neutral fibre NF is shifted forwards a little. The amount of stress in the tube cross-section is however minimal, so that the upper bore (even if it is a little remote from the neutral fibre NF) does not compromise the operational stability of the whole system. The portion of bending stress is significantly larger in the lower section. The neutral fibre NF is consequently close to the centre line. The amount of stresses is the greatest at the entrance into the cladding tube 28. It is clearly visible in combination with these embodiments that the bores (29, 29′, 29″) are located in the area of the smallest bending stress, i.e. close to the neutral fibre NF of the saddle support tube 16).

The illustrated parts are listed below in the list of reference numerals.

1 Pre-wiper ring 11 Wiping device 2 Wiper ring 23 Plastic bush 29, 29′, 29″ Bores 291 Countersink in the saddle support tube 16 3 Felt ring 4 Clamping nut 5 Cover of base body 51 Base body 52 Guide of locking pin 6 Tilting lever 61 Locking pin 62 Front end of the locking pin 63 First flattening (locking pin) 64 Second flattening 65 Axle of the locking pin 61 66 Axle of the tilting lever 6 68 Guide groove of the shafted cylinder 67 7 Rollers of tilting lever (2) 71 Recess GK for rollers of the tilting lever 8 Rollers of locking pin 9 Slotted slider 91 Slide of the slotted slider 92 Lug of the slotted slider 10 Compression springs of the slotted slider 12 Piston 13 Piston rod 14 Adjustment disc 15 Clamping nut 16 Saddle support tube 17 Sliding blocks 171 Grooves for guiding the sliding blocks 18 Fixing sleeve 19 Cover of pneumatic spring 20 Pneumatic spring outer tube 21 Resilient seal of piston rod 22 Pinhole closure (closure for bores 29, 29′, 29″ 221 Latching lug of the pinhole closure 23 Plastic bush 24 Fastening screw of pneumatic spring 25 Pneumatic spring valve 26 Bowden cable 261 Bowden cable eaves 27 Bowden cable holder 271 Fastening screws of Bowden cable holder (2) 272 Roller of slide 273 Slider (for slide) 274 Compression spring of slider 28 Cladding tube A28 Centre line of the cladding tube L Long hole V Locking device S Height adjustable saddle pole GF Pneumatic spring OR Upper tube H Lever FF Weight force of the rider FF FHO Force at the upper end of the cladding tube FHG Force of the sliding blocks exerted on the cladding tube FV Force absorbed by the locking pin ZS Tensile stress DS Compression stress NF Neutral fibre XX Guide bushing 

1. A height adjustable saddle pole consisting of two tubes which are telescopically slidable into another, that is to say 1.1. a cladding tube for accommodating a saddle support tube 1.2. a spring element acting upon the saddle support tube, 1.3. a locking device, which is arranged on the cladding tube with 1.3.1. a locking pin 1.3.2. a guide for the locking pin 1.3.3. means for adjusting the locking pin in a latched position and an unlatched position, whereas the locking pin is moved orthogonally with respect to and in the direction of the axis of the saddle support tube 1.4. whereas at least two axially spaced apart bores are provided in the saddle support tube for accommodating the locking pin, wherein 1.5. the locking pin in the latched position engages into one of the bores through a recess of the cladding tube, whereas it completely absorbs the axial forces of the saddle support tube, 1.6. whereas the bores are located in the area of the smallest stress of the saddle support tube.
 2. The height adjustable saddle pole according to claim 1, wherein the locking pin in the latched position accompanies the movement of the saddle support tube more or less in the direction and in the opposite direction of the cross product of the vector of the longitudinal axis of the cladding tube with the vector of the longitudinal axis of the locking pin.
 3. The height adjustable saddle pole according to claim 1, wherein the locking pin has a first flattening in the peripheral area of its front end.
 4. The height adjustable saddle pole according to claim 1, wherein the locking pin comprises second flattenings into the partial regions of its periphery on which the bores of the saddle support tube have the largest relative movement with respect to the locking pin.
 5. The height adjustable saddle pole according to claim 1, wherein the contour of the locking pin on its front end is adapted to the contour of the saddle support tube.
 6. The height adjustable saddle pole according to claim 1, wherein the locking pin is designed in such a way that it absorbs the load in direction of the longitudinal axis of the cladding tube over its surface in its guide.
 7. The height adjustable saddle pole according to claim 1, wherein a lever mechanism is provided for bringing the locking pin into the latched and into the unlatched position.
 8. The height adjustable saddle pole according to claim 6, wherein the lever mechanism is designed in such a way that it allows the movement of the bore caused by the load of the saddle support tube.
 9. The height adjustable saddle pole according to claim 1, wherein the adjustment of the locking pin is done via a sliding guide mechanism.
 10. The height adjustable saddle pole according to claim 1, wherein a portion of the mechanism for actuating the locking pin is arranged around the periphery of the cladding tube.
 11. The height adjustable saddle pole according to claim 1, wherein a Bowden cable is provided for adjusting the locking pin.
 12. The height adjustable saddle pole according to claim 1, wherein the spring element is a pneumatic spring.
 13. The height adjustable saddle pole according to claim 1, wherein the cladding tube is the saddle tube of a bicycle.
 14. The height adjustable saddle pole according to claim 1, wherein means are provided to prevent any twisting of the saddle support tube with respect to the cladding tube.
 15. The height adjustable saddle pole according to claim 1, wherein a pinhole closure is provided for sealing the bores, which opens in reaction to the force of the locking pin.
 16. The height adjustable saddle pole according to claim 1, wherein the upper end of the external tube of the pneumatic spring is fixed at the upper end of the saddle support tube.
 17. The height adjustable saddle pole according to claim 1, wherein a wiping device is provided, which comprises a felt ring.
 18. The height adjustable saddle pole according to claim 1, wherein the locking pin consists of a high performance plastic. 